A process of this type for producing fiber-reinforced foils, sheets or strips with a metal matrix is described in U.S. Pat. No. 4,733,816 and U.S. Pat. No. 4,499,156. In this case, the metal matrix is hot-pressed between and onto the fibers by an apparatus as described in U.S. Pat. No. 3,841,942. Silicon carbide fibers, silicon-coated silicon carbide fibers, silicon-carbide-coated boron fibers or boron-carbide-coated boron fibers are used as the fibers. Exclusively available as the matrix metal are titanium-based alloys.
The components finally produced from fiber-reinforced foils, sheets or strips are also referred to as metal-matrix components (MMCs).
The conventional process for producing fiber-reinforced foils, sheets or strips has the disadvantage that it is relatively complex, since it may require a number of steps for building up the fiber/foil structure. Furthermore, the attainable fiber volume content and the resulting mechanical properties are limited, since the densest arrangement of fibers cannot be achieved. Moreover, the distance between the fibers cannot be kept constant and the possibility of fibers touching and breaking cannot be ruled out. The deliberate alignment of the fibers in the required directions is possible only to a limited extent. This leads, inter alia, to fatigue cracks, lower break resistance and a shorter service life of the MMCs produced from the fiber-reinforced foils/sheets.
It is an object of the present invention to provide a process and an apparatus for producing a fiber-reinforced semifinished product in the form of metal strips, metal sheets, etc. such that, while avoiding the disadvantages mentioned, a low-cost process in which the reinforcing fibers are brought into a predetermined exact arrangement within the matrix of the semifinished product may be provided.